Method to increase phosphorus uptake in plants

ABSTRACT

The present invention provides a method to increase phosphorus uptake in plants. This can be accomplished by mining phosphorus both in the free and bound state from the soil solution surrounding the roots of a plant. The process of mining involves the release of phosphorus from the bound state and the solubilization of unbound phosphorus to facilitate uptake by the roots of a plant. The mining of phosphorus can be accomplished by providing a phosphorus solubilizing compound having: i) at least one natural root acid; ii) at least one vitamin and iii) at least one crystalline carbohydrate, to a portion of a plant. The phosphorus solubilizing compound can be applied to plants to extract available phosphorus from the soil. This product can be either a soluble liquid or a solid.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a divisional of U.S. Ser. No. 13/769,484 filed Feb. 18, 2013,and claims the benefit of U.S. Ser. No. 61/613,199 filed Mar. 20, 2012under 35 U.S.C. §119(e), both which are hereby specifically incorporatedby reference.

STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT

Not applicable

FIELD OF THE INVENTION

This invention relates to compositions that can mine the soil forphosphorus and reduce the need for the addition of synthetic granularfertilizers.

BACKGROUND OF THE INVENTION

In order to maintain healthy growth, plants must extract a variety ofelements from the soil. In terms of the quantity of nutrients needed,the “basic nutrients,” carbon, hydrogen and oxygen are the largest.Nitrogen, phosphorus and potassium are in the group known as the“primary nutrients” and are needed in the second largest quantity.However, in recent years, many states have become concerned about thewater pollution caused by the “run-off” of excessively appliedfertilizers, particularly nitrogen and phosphorus.

Of this group, phosphorus plays the key role in providing energy to therespiration cycle of the plant. No other element can replace phosphorusin this crucial role for plant life. Unfortunately, phosphorus isextremely reactive and forms very strong bonds with all metallicelements in the soil. This means it has limited availability for rootuptake and nature has developed several mechanisms for releasingphosphorus from the soil. The two most effective mechanisms forphosphorus release involve 1) microbial activity and 2) root exudates.These two mechanisms are symbiotic and work in concert to maximizephosphorus availability. The relationship between microbes and roots isunbelievably complicated and synergistic. Roots can exude compounds thatencourage specific microbe populations, capture specific nutrients, killpathogens, and repel insects. Microbes, for their part, excrete plantbiostimulants, fight off pathogens, and release nutrients from mineralsand organic matter. In view of environmental regulations, a need existsin the industry for compositions that can mine the soil for phosphorusand reduce the need for synthetic granular fertilizers.

SUMMARY OF THE INVENTION

Given the need in the industry, it is an object of the present inventionto provide a phosphorus solubilizing compound made of at least onenatural root acid, at least one organic acid and at least onecrystalline carbohydrate. It is another object of this invention toprovide a phosphorus mining composition made of a soluble blend of atleast one natural root acid, at least one vitamin, and at least onecrystalline carbohydrate, wherein said at least one crystallinecarbohydrate is inositol.

In another embodiment, this invention provides a phosphorus miningcomposition made by the process including the steps of: blending of atleast one natural root acid, at least one vitamin, and at least onecrystalline carbohydrate, wherein said at least one crystallinecarbohydrate is inositol in the presence of a compatibility agentselected from the group consisting of: chemicals with —OH groups and—NH2 amino acids to aid in the solubility of the composition.

In another embodiment, a method to increase phosphorus uptake in plantsis to provide including the steps of: providing a sufficient amount of aphosphorus solubilizing composition to a portion of a plant or adjacentto a portion of a plant to increase free soil phosphorus wherein saidphosphorus solubilizing composition consists essentially of a solubleblend of at least one natural root acid, at least one vitamin, and atleast one crystalline carbohydrate, wherein said at least onecrystalline carbohydrate is inositol.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

For a fuller understanding of the nature and desired objects of thepresent invention, reference is made to the following detaileddescription taken in conjunction with the accompanying drawing figures.

FIG. 1 shows tissue phosphorus levels after four weeks of treatment witha composition of the present invention.

FIG. 2 shows soil phosphorus levels four weeks after treatment with nogranular Phosphorus.

DETAILED DESCRIPTION OF THE INVENTION

The present invention may be understood more readily by reference to thefollowing detailed description of the invention. It is to be understoodthat this invention is not limited to the specific devices, methods,conditions or parameters described herein, and that the terminology usedherein is for the purpose of describing particular embodiments by way ofexample only and is not intended to be limiting of the claimedinvention. Also, as used in the specification including the appendedclaims, the singular forms “a,” “an,” and “the” include the plural, andreference to a particular numerical value includes at least thatparticular value, unless the context clearly dictates otherwise. Rangesmay be expressed herein as from “about” or “approximately” oneparticular value and/or to “about” or “approximately” another particularvalue. When such a range is expressed, another embodiment includes fromthe one particular value and/or to the other particular value.Similarly, when values are expressed as approximations, by use of theantecedent “about,” it will be understood that the particular valueforms another embodiment.

The present invention provides a method to increase phosphorus uptake inplants. This can be accomplished by mining phosphorus both in the freeand bound state from the soil solution surrounding the roots of a plant.The process of mining involves the release of phosphorus from the boundstate and the solubilization of unbound phosphorus to facilitate uptakeby the roots of a plant. The mining of phosphorus can be accomplished byproviding a phosphorus solubilizing compound having: i) at least onenatural root acid; ii) at least one vitamin and iii) at least onecrystalline carbohydrate, to a portion of a plant. The phosphorussolubilizing compound can be applied to plants to extract availablephosphorus from the soil. This product can be either a soluble liquid ora solid.

The art of the invention relates to the successful incorporation ofmultiple combinations of the natural exudates and excretions, into soilapplied product that can extract available phosphorus from the soil. Thefunctions of the root acids can be classified in three maincategories: 1) chelation or capturing of nutrients, 2) providing foodfor “beneficial microbes” and 3) repulsion or poisoning of pathogens andinsects. Root acids include:

Exuded Root Acid Acetic Formic Oxalic Hydrocyanic Malic Citric AsparticGluconic Pimelic Succinic Tartaric Fumaric Glycolic Piscidic AldonicValeric Aconitic Lactic Pyruvic Glutaric Malonic Erythronic Tetronic

One of the plant's top priorities is to insure a supply of phosphorus todrive energy needs and bolster the respiration cycle. Citric acid andmalic acid together comprise over 95% of the total root exudates.However, there are several of these acids that focus only on the releaseof phosphorus, namely, citric, fumaric, glycolic, piscidic, aldonic, andmalonic. In the present invention, at least one of citric, fumaric,glycolic, and aldonic acid are preferred.

In addition to the root acids above, the plant can and will exude thefull array of 23 amino acids, 12 different enzymes, 6 different sugars,3 different alcohols, 4 different aldehydes, and 3 different flavanoids.However, the total of all these (plus the 21 root acids without thecitric and malic) make up only 5% of the exudate load. These rootexudates act both directly and indirectly on the microbes in the soil tooptimize the processing of minerals and enhance the microbialexcretions. In the mycchorizae, beneficial microbes excrete manydifferent compounds aimed at keeping the plant healthy.

Here is a summary of a few of those compounds:

Compound Thiamine (Vitamin B₁) Riboflavin (vitamin B₂) Nicotinic acid(vitamin P) Folic acid (vitamin B₉) Ascorbic acid (Vitamin C) Vitamin B₆Biotin (vitamin H) Pantothenic acid (vitamin B₅) Carotene (vitamin A)Tocophoryl (vitamin E) Vitamin K Amino acids Inositol Auxins Glutaricacid Formic acid Valeric acid

As with the root exudates, there are several of these excretions thatare related to the release and use of phosphorus. These include:riboflavin (vitamin B₂), folic acid (vitamin B₉) and pantothenic acid(vitamin B₅).

Crystalline carbohydrate are sugars that are soluble in water. Inparticular, inositol binds with phosphate ion for transport through theroots and throughout the plant.

The incorporation of these exudates and excretions into a soil appliedproduct enhances the natural release of plant-available phosphorus andeliminates the need for the synthetically produced phosphorusfertilizers. This product can be either a soluble liquid or a drypowder. Both forms have their advantages and disadvantages.

The liquid version of the product provides a much quicker response toplant growth. The soluble constituents can penetrate the soil and enterthe root zone as it is applied and watered in. However, solubility ofseveral of the constituents is low and the successful blending of theseingredients is part of the art. Riboflavin, for example, is nearlyinsoluble in water, but is completely soluble in isopropyl alcohol.Pantothenic acid is slightly soluble in water, but is completely solublein methylethylamine.

The successful blending of the final product then requires the additionof chemicals with —OH groups and —NH2 amino acids to aid in thesolubility of the overall product. Examples of chemicals providingsolubilization with an —OH groups are differing molecular weights ofpolyethylene oxide, polyethylene glycol (PEG) and polypropylene glycol(PPG). Additionally, examples of —NH2 amino acids that aid in thesolubility of the overall product include amino acid blends that aremade of leather collagen and/or keratin. It is these type of compoundsthat are considered “Compatibility Agents.”

A typical product blend can contain components in these ranges:

Raw Material Weight % Range Water 40-87 Inositol 10-20 Citric Acid  2-10Fumaric Acid 0-4 Malonic Acid 0-4 Glycolic Acid 0-4 Humic Acid 0-4Aldonic Acid 0-4 Riboflavin 0-2 Folic Acid 0-2 Pantothenic Acid 0-2Compatibility 1-5 Agent

In another embodiment, a dry powder version is used. The dry powderversion is much easier to blend since the solubility issues have beenremoved. However, the final product must be easily slurried without thebuild-up of clumps or precipitates. Part of the art is the incorporationof dispersion aids to insure a properly slurried product. A typicalrange of recipes can be seen in the following table:

Raw Material Weight % Range Inositol 10-20 Citric Acid  5-15 FumaricAcid 0-6 Malonic Acid 0-6 Glycolic Acid 0-6 Aldonic Acid 0-6 Humic Acid0-6 Riboflavin 0-4 Folic Acid 0-4 Pantothenic Acid 0-4 Dispersion 25-85Agent

The “Dispersion Agent” is required to prevent caking and clumping duringthe dissolving process. Quick dispersion of the ingredients while addingwater is required to minimize any form of agglomeration and aid in thesolubility. Examples of dispersion agents include humic acid, starchand/or glucoheptose.

EXAMPLE 1 Lab Batch Test

A lab batch was prepared using several organic acids to release thephosphorus and sugars to chelate and transport the nutrient. A simpleexperiment was performed to test the phosphorus releasing capabilitiesof the composition of the invention.

The trial batch was powder placed in 1-gallon jugs. Water was then addedto the jug to dissolve the product. There were no issues dissolving thecomposition of the present invention. Two different dosages were appliedto a small soil plug in the lab. The beginning phosphorus content in thesoil was 8 ppm. The results, in Table 1, show that the product increasesthe availability of several key nutrients in the soil—includingphosphorus.

TABLE 1 Nutrient content, meq/l No treatment Run 1 Run 2 % IncreasePhosphorus 0.14 0.19 0.17 28.6 Sulfate 0.96 2.19 1.59 96.8 Manganese0.09 1.01 1.16 1100.0 Iron 1.03 2.32 2.35 227.0 Calcium 0.84 1.01 0.9516.7 Silicate 3.49 6.2 6.4 80.0

EXAMPLE 2 Evaluate the Ability of a Phosphorus Solubilizing Compound toMaintain a Greater Pool of Plant-Available Phosphorus for Turf-GrassUptake

The experiment was conducted at the Auburn University Plant ScienceResearch Center (PSRC) greenhouse facility, located on the Auburncampus. A Decatur soil (fine, kaolinitic, thermic Rhodic Paleudult witha high phosphorus fixing capability (via Al/Fe sesquioxides)) was usedfor the experiments. An initial soil test result revealed a soil pH of6.0, soil P (Mehlich) of 11 pounds per acre (Very Low), soil K of 253pounds per acre (Very High) and soil magnesium, and calcium of 300 and1715 pounds per acre, respectively.

The experiment design was a 5×3 factorial of phosphorus rate andphosphorus solubilizing materials. Phosphorus rates were 0, 30, 60 and90 pounds P₂O₅ per acre, mixed with the soil surface (top one inch) in aone-time addition as triple super phosphate (TSP) (0-45-0). Phosphorusrates were combined with one of three solubilizing materials: 1) none,2) composition of the present invention (at three rates, labeled, 2× and4×), and, 3) AVAIL (Southern States, Inc). One of the goals of theexperiment is to determine the optimum dosage for phosphorus release.

The composition of the present invention was applied at three rates,which were 0.1 gram per pot, 0.2 grams per pot and 0.4 grams product perplot. This corresponded to the labeled rate, and 2× and 4× that labeledrate.

The test was arranged in a complete (without phosphorus fertilizer)factorial design of 4 phosphorus rates×4 phosphorus solubilizers, for atotal of 16 treatments in the study. Each treatment was replicated 3times. Destructive sampling of the study was performed (3 times, atweeks 4, 8 and 12 after fertilization) there were 144 pots in each test.The entire experiment was repeated twice.

An experiment unit (pot) was four inches in diameter and six incheshigh, with each pot filled to within one inch of the rim with the groundand sieved soil. The same weight of soil was placed in each pot. Potswere watered to prevent water leaching from the bottom of each pot. Allpots were watered to maintain soil water status at around 80% belowfield capacity.

Phosphorus fertilizer rates were determined for each treatment, and thatphosphorus (as TSP) was mixed in the top one inch of soil. Thecomposition of the present invention was added by mixing each amountwith a small amount of water (20 mL) and poring that on the soil in eachpot. The same amount of water was applied to every pot. Twenty seeds of‘Marshall’ annual ryegrass were seeded in the top of each pot, andlightly watered until emergence. Once the experiment was initiated allpots were watered with a phosphorus deficient Hoaglands solution tosupply 1/10^(th) pound of N per 1,000 square feet per week.

Table of Activities: Date Activity - Run 1 Date Activity - Run 2 Jan.13, 2011 Initiated Experiment Feb. 17, 2011 Initiated Experiment Jan. 31Fertilized with Feb. 28 Fertilized with Hoaglands Hoaglands Feb. 9 Week4 Harvest Mar. 7 Fertilized with Hoaglands Feb. 14 Fertilized with Mar.14 Fertilized with Hoaglands Hoaglands Feb. 21 Fertilized with Mar. 16Week 4 Harvest Hoaglands Feb. 28 Fertilized with Mar. 21 Fertilized withHoaglands Hoaglands Mar. 7 Fertilized with Mar. 28 Fertilized withHoaglands Hoaglands Harvested extra tissue (week 6) Mar. 9 Week 8Harvest Apr. 4 Fertilized with Hoaglands Mar. 14 Fertilized with Apr. 11Fertilized with Hoaglands Hoaglands Ma. 21 Fertilized with Apr. 12 Week8 Harvest Hoaglands Mar. 28 Fertilized with Apr. 18 Fertilized withHoaglands Hoaglands Apr. 4 Fertilized with Apr. 25 Fertilized withHoaglands Hoaglands Apr. 6 Week 12 Harvest May 2 Fertilized withHoaglands May 9 Week 12 Harvest

Data collection involved dry weight of harvested ryegrass roots andtop-growth (3 separate measurements), performed as destructive harvestsat weeks 4, 8 and 12. At each sampling the plants were removed and rootsand shoots (top-growth) separated, washed, dried and weighed. Soilsamples were collected for subsequent extraction (described below). InRun 2 top-growth was sufficient that an additional harvest was needed atWeek 6. This top-growth was also analyzed for phosphorus content. Atthis time the plants were merely clipped, and a destructive harvest wasnot done. Tissue phosphorus content of top-growth using standard drycombustion and analysis techniques. Tissue phosphorus was determined viaInductively Coupled Plasma Spectrometry (ICP) soil phosphorusavailability as extracted with: 1) CaCl₂ (labile phosphorus), and, 2)Mehlich-I extractant (SE standard soil test extractant for phosphorus).Phosphorus was determined using standard Molybdate-blue colortechniques.

The most spectacular results from the trial revealed an increase of upto a 26% increase in tissue levels and a 61% increase in the free soilphosphorus without the supplement of phosphorus fertilizers as shown inFIGS. 1 and 2.

These and other aspects, features and advantages of the invention willbe understood with reference to the detailed description herein, andwill be realized by means of the various elements and combinationsparticularly pointed out in the appended claims. It is to be understoodthat both the foregoing general description and the following detaileddescription of the invention are exemplary and explanatory of preferredembodiments of the invention, and are not restrictive of the invention,as claimed.

The invention claimed is:
 1. A method to increase phosphorus uptake inplants comprising: providing a sufficient amount of a composition to aplant or adjacent to a plant to increase free soil phosphorus whereinsaid composition consists essentially of a soluble blend of at least onenatural root acid, at least one vitamin and at least one crystallinecarbohydrate, wherein said at least one crystalline carbohydrate isinositol.
 2. The method of claim 1 further comprising adding water tosaid composition.
 3. The method of claim 1 further comprising adding acompatibility agent selected from the group consisting of: polyethyleneoxide, polyethylene glycol (PEG) and polypropylene glycol (PPG) to saidcomposition.
 4. The method of claim 1 further comprising addingsufficient amount of a dispersion agent to prevent caking and clumpingof said composition to said composition.
 5. The method of claim 4wherein the dispersion agent is selected from the group consisting ofhumic acid, starch and glucoheptose.
 6. The method of claim 1 whereinsaid at least one root acid is selected from the group consisting of:acetic, formic, oxalic, hydrocyanic, malic, citric, aspartic, gluconic,pimelic, succinic, tartaric, fumaric, glycolic, piscidic, aldonic,valerie, aconitic, lactic, pyruvic, glutaric, malonic, erthronic andtetronic acid.
 7. The method of claim 1 wherein said vitamin ispantothenic acid.
 8. The method of claim 1 wherein said vitamin isriboflavin.
 9. The method of claim 1 further comprising the step ofblending the composition with a phosphorus deficient fertilizer.
 10. Themethod of claim 3 wherein the composition in a weight percent rangeconsisting essentially of: water 40-87; inositol 10-20; citric acid2-10; fumaric acid 0-4; malonic acid 0-4; gycolic acid 0-4; humic acid0-4; aldonic acid 0-4; riboflavin 0-2; folic acid 0-2; pantothenic acid0-2; and a compatibility agent 1-5.
 11. The method of claim 4 whereinthe composition in a weight percent range consisting essentially of:inositol 10-20; citric acid 5-15; fumaric acid 0-6; malonic acid 0-6;gycolic acid 0-6; aldonic acid 0-6; humic acid 0-6; riboflavin 0-4;folic acid 0-4; pantothenic acid 0-4; and a dispersion agent 25-85. 12.The method of claim 11 wherein said dispersion agent is selected fromthe group consisting of humic acid, starch and glucoheptose.